1. Field of the Invention
The present invention relates to a molding press, and, more particularly, to a molding press for large injection molds.
2. Description of the Related Art
Molding presses are used as part of a manufacturing process for the production of parts made from thermoplastic or thermosetting plastic materials. Material granules are fed into a heated container where they are mixed, and then pressurized into a mold cavity where the material cools and hardens to the configuration of the cavity. A toolmaker machines the mold from metal to form the features of the desired part. Injection molding techniques are used for the manufacture of a variety of parts, from the smallest component to entire body panels of vehicles.
A press is used to temporarily hold mold halves together while the heated material is injected under high pressure. The press has to hold the mold halves together without allowing any separation of the mold halves during the injection of the material to avoid the formation of flash, and to avoid the manufacture of scrap parts. In order to be effective the press has to be rigid and able to provide a significant pressure to hold the mold together.
Advantages of injection molding processes are relatively high production rates, repeatable tolerances, the use of a wide range of materials, the use of less skilled labor, low scrap losses, and the parts having a finished look after coming from the mold. Disadvantages of the injection molding process include equipment investment, environmental concerns, and energy costs. A difficulty in molding large parts is the need for a repeatable, reliable system for positioning and holding the mold.
What is needed in the art is a large molding press capable of repeatable consistent positioning of the mold portions for the efficient molding of large parts.